Pressure operated packer



April 1959 N. A. NELSON ET AL 2,880,805

PRESSURE OPERATED PACKER Filed Jan. 3, 1956 2 Sheets-Sheet 1 FIG. F/G.-2.

\ .3/ i M 35 I INVENTORS.

Norman A. Nelson, BY Joe W Gibbs,

ATTORNEY PRESSURE OPERATED PACKER Norman A. Nelson, Genoa, and Joe W. Gibbs, Houston, Tex.; said Nelson assignor, by mesne assignments, to Jersey Production Research Company, Tulsa, Okla., a corporation of Delaware Application January 3, 1956, Serial No. 557,131

. 6 Claims. (Cl.'1661 20) This invention relates to a new and useful well packer. More particularly this invention relates to an improved well packer utilizing pressure operated slips for setting the well packer, which slips are operated entirely by pressure applied to the slips, there being no dependence upon any mechanical element directly related to the slips for causing the expansion of the slips to set the well packer.

The pressure operated slips permit setting the packer United States PatentO said mandrel below the longitudinally extended portion of increased diameter. A tubular body is disposed about said mandrel with said tubular body having mounted therein, in its inner periphery, a lug pin which is initially located in the lower curved portion of the 0 slot. When it is desired to set our new and improved well packer, the p tubular mandrel is first moved upwardly, then rotated and ,then lowered so as to move the 0 slot, relative to the lug pin, to a position which permits the application of pressure to pressure operated slips contained within the tubular body, which slips set the packer. Two modifications of our new well packer utilizing pressure operated slips are shown.

Other objects and a fuller understanding of the invention may be had by referring to the following description and claims, taken in conjunction with the accompanying position;

Fig. 2 is a side elevational view partly in section showing the embodiment of Fig. l in the set position;

Fig. 3 is an elevational view of the mandrel showing the 0 slot machined in said mandrel;

Fig. 4 is a side elevational view partly in section showing a second embodiment of our new pressure operated packer in the unset position; and Fig. 5 is a side elevational view partly in section showing the embodiment of Fig. 4 in the set position.

Referring to the drawings Fig. 1 shows a well pipe or casing 10 into which our new pressure operated packer may be lowered. The packer is lowered by means of a drill pipe string or other meanswhich has attached thereto a mandrel 11. The mandrel 11 may have a longitudinally extended portion thereof of increased diameter 12. The longitudinally terminates with a shoulder 13, which shoulderis located just above the upper curved portion of a 6 slot 14., In Fig. 1 thenew improved packer is shown in its position as it is lowered down a borehole in which position it is in the unset position.

extended portion 12 of increased diameter The packer assembly includes a tubular member 15 which is disposed about'the mandrel 11 coaxially therewith. The tubular member 15 has formed therein an upper confined space or recess 16 and a lower confined space or recess 17. Disposed within each of the spaces 16 and 17 is a uni-direction or oneway packing seal 18 which may suitably be chevron packing or the like. Though the packing seal 18 is shown as a uni-direction packing seal, it is to be understood that any other type of structure giving the uni-directional or one way directional effect may be utilized. The inside diameter of the tubular member 15, including the inside diameter of the uni-direction packing seals 18, is greater than the outside diameter of the lower portion of tubular mandrel 11. Hence, a space 35 is provided between the mandrel 11 and the tubular body 15. Connected to the longitudinal extremities of tubular member 15 are packing seal cups 19. Also mounted within the tubular member 15 are a plurality of pressure operated slips 20. The pressure operated slips 20 are located within recesses formed within the tubular member 15. Each pair of slips is connected by a slip return spring 21 which is mounted upon a slip guide member 22 by means of a screw 23. Provided within the tubular member 15 at a point just below the upper seal cup 19 is a pressure equalizing port 24. The pressure equalizing port 24 extends completely through the'tubular member 15 to the space 35 between the outside diameter of mandrel 11 and the inside periphery of tubular member 15. Hence, it can be seen that any pressure differential across the packer cups 19 is equalized by means of pressure equalizing port 24 when the packer is in the unset position. Mounted within the lower portion of tubular member 15, just above the lower packing seal 19, is a lug pin 25, the inner portion 26 of lug pin 25 extending into the 0 slot 14. In the unset position the lug pin 25 is located within the lower curved portion 27 of 0 slot 14.

In operation, as the mandrel 11 and tubular member 15 are lowered down the pipe or casing 10 any fluids contained within the pipe 10 pass through the hollow center of the mandrel 11 and out the circulation ports 28, the fluids thereby passing through the pipe 10 with very little resistance or friction. The premature setting of the seal cups 19 and pressure operated slips 20 is prevented by means of the equalizing port 24 which prevents a pressure differential from being developed across the seal cups 19,

When it is desired-to set the packer shown in Fig. 1 the tubular mandrel 11 is first rotated in a direction so as to position the lug pin 25 in the vertical portion of the 0 slot 14 and then lowered thereby moving the 0 slot 14 relative to the lug pin 25 until the lug pin 25 is located within the upper curved portion of the 6 slot, as shown in Fig. 2. As the mandrel 11 is rotated and lowered, the tubular body 15 of the packer is maintained in position by the friction of the seal cups 19 which are in contact with the pipe 10 and also by the friction of the drag springs 30 which are also in contact with the pipe 10.

The set position of the new packer shown in Fig. 1 is illustrated in Fig. 2. As shown in Fig. 2 the 0 slot 14 positions the tubular member 15 adjacent the longitudinally extended portion of increased diameter 12 of mandrel 11. Hence the equalizing port 24 is positioned adjacent the equalizing port sealing surface 31 on mandrel 11. :Because the inside diameter of the tubularbody 15 is substantially equal totthe outside diameter of1 the equalizing port sealing surface .31'and a pressure seal is efiected by elements 32-on-sealing surface 31, the equalizing port 24 is in'effect closed and any pressure 'differene tial across the seal cup 19 can no longer be equalized;

1 Sealing rings 32 thus provide a pressure-tight seal btween tubular member 15 and theequalizingport sealing sure through space 35 and against the inside periphery of the pressure operated slips 20. The equalizing port by-passes begin just above the upper extremity of the tubular member 15 and terminate just above the uppermost packing seals 18. The packing seals 18 are the type of packing seals which will permit the transmission of pressure toward the pressure operated slips '20 but will prevent the transmission of pressure through the packing seals away from the pressure operated slips 20. As can be seen in'Figs. l and 2, the/chevron packing 18 in recesses 16 and 17 are arranged such that pressure can be "exerted toward the pressure operated slips 20 but will resist pressure exerted away from slips 20. As shown more clearly 'in Fig. '2, any pressure operating against the packing seals 18 away from the pressure operated slips 20 will effect a seal-tight engagement of the seals '18 against the outside periphery of the increased diameter portion 12 of mandrel 11, thus preventing the outward transmittal of pressure.

The pressure operated slips 20 are radially expanded by means of pressure exerted through the equalizing port by-passes 33, which pressure is transmitted through the upper packing seal 18 and space 35 to radially expand the pressure operated slips 20. The application of pressure against the ressure operated slips 20 cause the slips to be radially expanded to thereby set the packer. holding .force of the slips is proportional to the maximum pressure differential across the packer so that the greater the pressure the greater the holding force of the slips.

When it is desired to release the packer the tubular mandrel 11 is rotated in the appropriate direction and then raised to position the lug pin 25 in the lower curved portion of slot 14, as shown in Fig. 1. The tubular member 15 is then positioned adjacent the decreased diameter portion of mandrel 11 and pressure contained within the slips 20 is released through the space defined by the inner periphery of the tubular member 15 and the outer periphery of the mandrel 11. Since the inner periphery of the packing seals '18 is now greater than the outer periphery of the tubular mandrel 11 the pressure contained within the pressure operated slips 20 can be released through the packing seals 18. The unsetting of the pressure operated slips 20 is aided by the slip return springs '21 which were tensi'oned when the pressure operated slips were radially expanded.

Referring to Figs. 4 and 5, wherein like numerals are referring to like parts, there is shown a second embodiment of our new pressure operated packer. The embodiment shown in Fig. 4 is different from thatshown in Fig. 1 in that no uni-directional pressure effect is needed. Also the equalizing port 40 is located within the tubular member 15 between the upper section and lower section of slips 20 rather than between the upper section of slips and the upper seal cups as is the case with the embodiment shown in Fig. 1. In the embodiment of Fig. 4, no equalizing port by-passes are needed. However, the manner of operation of the embodimentshown in Fig. 4 is similar to that of the embodiment of Fig. 1. In the unset position a pressure differential is prevented from developing across the seal cups 19 by means of the equalizing port 40 and the space between the inner periphery of the tubular member 15 and the mandrel 11. When it is desired to set the pressure operated slips .20 the mandrel 11 is rotated and lowered until .the lug pin 15 is located within the 6 slot .14 as shown .in Fig. 55. The. rotation and loweringxo'f mandrel 11 positions the equalizing port .40 adjacent the longitudinally extended portion of increased diameter 41 thereby sealing off. the pressure equalizing port 40. .Since in theset position shownin Fig. .the inside diameter of the tubular member and slips is greater than the outside diameter The of the mandrel 1-1 above and below the area of'increased diameter 41 on mandrel 11=any pressure which is exerted either above or below the seal cups 19 will be exerted respectively against the slips 20 located above or below the equalizing port 40 to thereby radially expand slips 20 to set the packer.

When it is desired to unset the packer the mandrel 11 is rotated and raised to position the lug pin 25 in the lower curved portion of 0 slot 14 to thereby locate the equalizing port 40 as shown in Fig. 4 thus permitting the release of pressure from the slips 20 causing the slips to be disengaged from pipe 10.

Hence, it can be seen we have invented a new and useful well packer which has pressure operated slips. The pressure operated slips are operated entirely by the application of pressure and have no mechanical means connected or associated therewith for moving the slips .to engage the walls of a pipe or casing.

Although we have described our invention with .a certain degree of particularity, it is understood that the present disclosure has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to Without departing from the spirit and the scope of the invention as hereinafter claimed.

What we wish to claim is:

1. A device for sealing off a cased well bore comprising a hollow mandrel provided with an opening fluidly communicating the interior and exterior of said mandrel, a tubular member surrounding said mandrel and forming an annulus therebetween, said mandrel being movable from a first to a second position relative to said tubular member, upper and lower spaced-apart packers arranged on said tubular member adapted to seal off the space between said packers formed between said tubular member and said casing, said tubular member being provided with an opening, at least one pressure operated slip arranged on said tubular member between said packers adapted to move outwardly to grip said casing in response to a fluid pressure differential existing between said annulus and said space between said packers, means interconnecting said mandrel and said tubular member adapted to permit said mandrel to move relative to said tubular member from said first to said second position, said packers also functioning to hold said tubular member against movement when said mandrel is moved relative to said tubular member, said mandrel being provided with an enlarged outer diameter portion providing a sealing surface, said tubular member opening fluidly communicating said annulus and the space between said packers when said mandrel is in said first position, first and second sealing means arranged on said tubular member above and below, respectively, said tubular member opening, said first and second sealing means engaging said sealing surface to seal off fluid communication between said annulus and the space between said packers through said tubular member opening when said mandrel is in said second position, first one-way sealing means arranged on said tubular member between said second sealing means and said slip adapted to engage said sealing surface when said mandrel is in said second position to permit downwardly directed fluid flow and to prevent upwardly directed 'fiuid flow, second one-way sealing means arranged on said tubular member between said lower packer and said slip adapted to engage said sealing surface when said mandrel is in said second position to permit upwardly directed fluid flow and to prevent downwardly directed 'fiuid flow, and .by-pass means arranged on said mandrel providing 'fiuid communicationbetween thespace above the upper packer and said annulus below the second sealing means, said mandrel opening fluidly communicating the .interior of the mandrel and thespa-ce above the upper packer when said mandrel is in said first position and 'fluidly communicating the interior of said mandrel and said annulus below said second one way sealing means when said mandrel is in said second position.

2. A device as recited in claim 1 wherein said means interconnecting said mandrel and said tubular member comprises a C-slot formed on said mandrel and a pin member connected to said tubular member positioned in said slot.

3. A device as recited in claim 1 wherein said tubular member is provided with drag means engaging said casing adapted to aid said packers in holding said tubular member against movement when said mandrel is moved relative to said tubular member.

4. A device for sealing off a cased well bore comprising a hollow mandrel provided with an opening fluidly communicating the interior and exterior of said mandrel, a tubular member surrounding said mandrel and forming an annulus therebetween, said mandrel be ing longitudinally movable from a first to a second position relative to said tubular member, upper and lower spaced-apart packers arranged on said tubular member adapted to seal oifthe space between said packers formed between said tubular member and said casing, said tubular member being provided with an opening, first pressure operated slips arranged on said tubular member between said upper packer and said tubular member opening adapted to move outwardly to grip said casing in response to a fluid pressure differential existing between said annulus and said space between said packers, second pressure operated slips arranged on said tubular member between said lower packer and said tubular member opening adapted to move outwardly to grip said casing in response to a fluid pressure difierential existing between said annulus and the space between said packers, means interconnecting said mandrel and said tubular member adapted to permit said mandrel to move relative to said tubular member from said first to said second position, said packers also functioning to hold said tubulat member against movement when said mandrel is moved relative to said tubular member, said mandrel being provided with an enlarged outer diameter portion providing a sealing surface, said tubular member opening fluidly communicating said annulus and the space between said packers when said mandrel is in said first position, first and second sealing means arranged on said tubular member above and below, respectively, said tubular member opening, said first and second sealing means engaging said sealing surface to seal off fluid communication between said annulus and the space between said packers through said tubular member opening when said mandrel is in said second position, said mandrel opening fluidly communicating the interior of said mandrel and the space above the upper packer when said mandrel is in said first position and fluidly communicating the interior of said mandrel and said annulus below said second sealing means when said mandrel is in said second position.

5. A device as recited in claim 4 wherein said means interconnecting said mandrel and said tubular member comprises a C-slot formed on said mandrel and a pin member connected to said tubular member positioned in said slot.

6. A device as recited in claim 4 wherein said mandrel is provided with drag means engaging said casing adapted to aid said packers in holding said tubular member against movement when said mandrel is moved relative to said tubular member.

References Cited in the file of this patent UNITED STATES PATENTS 2,352,700 Ferris July 4, 1944 2,704,580 Brown Mar. 22, 1955 2,716,456 Brown Aug. 30, 1955 -.---'.----.'--t'r'--r-.- y 

